The hinges may be a bit industrial looking but they do work. I avoided countersunk heads because it's a nightmare cutting big countersinks in stainless plate. Perhaps some paint will help to disguise them.
Next sail will be in mild weather because this is one part of an outrigger canoe that do not want to fail. I've left enough metal in the brackets that I would be able to go to larger size pins if I see any distortion in the 5/16" (8mm) ones I have now.